>>1408204If you're specifically looking for a mountain bike, the very first thing you should do is see where you would ride one. If you're a beginner, you'll want recommended mountain or offroad trails. National parks are a decent start. At your price range you'll almost exclusively be looking for something used. With mountainbiking you can't really just hop on something and hope it'll work out like a road bike. You need a solid frame with a solid braking and gearing system that can handle a good beating. You could probably get by with a 29er off of Bikes Direct if you're satisfied with being limited to intermediate trails at best. If you're over 5'8", Walmart bikes just won't fit you, even if you could find one that doesn't have a "don't use on trails" sticker.
