Now, seven years later, Lang has advice for others desiring a big slice of Big Sky Country, where owning a ranch has gained a certain cachet from celebrity buyers such as Ted Turner, Tom Brokaw and David Letterman.

''I think when you come as an outsider, the most important thing is to admit what you are and admit what you aren't,'' Lang says in a new, short film produced by the state wildlife agency and a cattlemen's group. ''I'm not a rancher by background, and I'm learning how to be a rancher from my friends here in the community.''

The film, ''Owning Eden,'' is an attempt to help wealthy outsiders shopping for ranches understand the big picture of life in rural Montana.

''Owning Eden'' evolved from concern about changes happening in the state as traditional ranchers, some with land and customs passed through generations, sell their properties - often at prices that astonish their neighbors.

One real estate agency's ranch listings include 5,700 acres east of Great Falls for $7.2 million; 30,000 acres in the heart of Montana for $12.5 million; and 416 acres near Livingston for $3.8 million. The colossus is a 17,000-acre spread near the Idaho border, already in nonresident hands for some time and listed at $25.9 million. That includes a house featured in Architectural Digest.

When newcomers invest that kind of money, traditional ranching often ceases. Sometimes, long-standing customs such as opening the land to public hunting evaporate as well.

''We feel there is a role we can play in reaching out to these people,'' said Steve Pilcher, executive vice president of the Montana Stockgrowers Association, which produced the film with the Montana Department of Fish, Wildlife and Parks. Often, the newcomers ''don't realize they're buying more than just the real estate.''

New arrivals remain a minority by a wide margin, according to the stockgrowers' association, which says 83 percent of Montana ranches have been in the family for more than 25 years, and 10 percent for more than a century.

With stunning scenery, the film portrays ranching as a rich part of Montana's heritage, woven with neighborliness and respect for the land. The beauty that draws people here is ''the product of conservation, not preservation,'' the narrator says in an apparent pitch to people who may envision converting ranches into sanctuaries.

The tone of the film, featuring longtime ranchers Chase Hibbard and Maynard Smith along with Lang, is friendly.

''This needs to be real nonthreatening, informational,'' said Ron Aasheim of Fish, Wildlife and Parks. ''We're not in the business of telling people what to do.'' He hopes real estate offices, conservation groups and others in contact with would-be ranch owners will help circulate the film.

''In my experience, the first thing that happens is the padlock goes on the gate,'' Hibbard, who ranches near Helena, says to the camera. ''I can understand why they feel that way when they come here. It's a major expenditure, they may come from a place where you have to protect your property rights, you have to protect the safety of your person. We're not there, yet, in this state.''

The film suggests new ranch owners allow hunting as a way to help manage wildlife, particularly elk, that will roam and feed at neighboring ranches, where the forage is needed for cattle. Another message: Control your weeds. The weed-wildflower called Dalmatian toadflax may provide a nice splash of color, but it disregards property lines.

''When you're across the fence from somebody, if he doesn't take care of his weeds, you're going to have them,'' said Smith, who ranches in the Dillon area of southwestern Montana and has the weathered look of a Western traditionalist.

Hibbard suggests lockouts involve not just gates; sometimes they're found in attitudes, as well.

''Make some friends in the community. Be sensitive to the values that existed before you came, and be supportive of those values instead of locking them out,'' he says, reinforced by the narrator's appeal for newcomers to preserve ''the values that led you to Montana in the first place.''

Lang, whose Infinity Financial Technology software company was bought by SunGard Data Systems in 1998 for about $313 million in stock, said in a telephone interview that he agreed to be in the film because newcomers need to be informed.

''I can imagine how unsettling it is for Montanans, especially multigenerational Montanans, to see people come in and treat this like it's some kind of suburban playground,'' Lang said from Sun Ranch, which he bought from actor Steven Seagal. The ranch, about 40 miles from Yellowstone National Park, is a part-time home for Lang, who is in California often.

''Urban people are tightly packed, very densely populated and they protect their own with more than a white picket fence,'' he said. ''When we come here there is a completely different ethic - that you protect each other.''

At the multistate real estate agency Hall and Hall, manager Jim Taylor said the purchase of Montana ranches by newcomers who pay handsomely has been happening for years. Ted Turner's ranch ownership helped shine a spotlight on the state for other celebrities looking to buy, said Taylor, who was involved in Turner's 1989 purchase of the Flying D Ranch near Bozeman.

Taylor has not seen ''Owning Eden,'' but said he probably will be comfortable with the film if he does not detect an ''edge'' in it.

He finds that the wealthy buy land in Montana for reasons beyond natural splendor, wildlife, getting away and the cowboy mystique. ''You have something that is very fundamental,'' he said. ''People say that to own a beautiful piece of land is like owning a piece of fine art,'' but with the added dimension of permanence.

It's been a long time since prices for Montana land reflected how many cows it could support, Taylor noted.

''Now somebody will say 'I'll pay a thousand for the view, and another $5,000 because it doesn't have roads through it, and $10,000 because I can get there easily from the airport.'''

Rich newcomers with ranches have a responsibility ''not to throw their money around and not to upset local customs,'' Taylor said. ''We [Montanans] have a responsibility to welcome these people and help them become part of the communities."