Look for end of the season sales, or better yet, know someone that works for a supplier or store that can get you a decent discount. Mountain bikes are insanely expensive, but for local stores there mostly isn't a big profit margin (at least not here, Norway). The manufacturers themselves probably have a lot better profit margins, but I do not know enough to say anything about it. At this point, any "known-brand" mountain bike over or around $2000 new is a really solid bike that will work great and last a long time if taken care of properly. Above that you start to see carbon frames, higher end gruppos and mostly weight savings.
For example a bike with a Shimano SLX groupset is basically as good as one with the XT groupset (one step up), the XTR groupset is lighter and costs way more.
the Shimano SLX groupset is comparable to SRAM's X9 groupset in performance and price.
Getting into the sport I would go for a hardtail (no rear suspension) first. They are a lot cheaper, and you will get more bike for the money. Spend $2000 on a hardtail and you have a really great and light bike with a near top-end groupset, but if you spend $2000 on a full-suspension bike you will get less bike for the money, and a hardtail is good for beginners anyway. When you do not have rear suspension you have to learn how to keep your weight on the bike and how to pick the best lines down, and a full-suspension bike is a lot more forgiving that way. I can ride down stuff on my FS bike I'd never dream of doing on my hardtail.
For example a bike with a Shimano SLX groupset is basically as good as one with the XT groupset (one step up), the XTR groupset is lighter and costs way more.
the Shimano SLX groupset is comparable to SRAM's X9 groupset in performance and price.
Getting into the sport I would go for a hardtail (no rear suspension) first. They are a lot cheaper, and you will get more bike for the money. Spend $2000 on a hardtail and you have a really great and light bike with a near top-end groupset, but if you spend $2000 on a full-suspension bike you will get less bike for the money, and a hardtail is good for beginners anyway. When you do not have rear suspension you have to learn how to keep your weight on the bike and how to pick the best lines down, and a full-suspension bike is a lot more forgiving that way. I can ride down stuff on my FS bike I'd never dream of doing on my hardtail.