Yup, you should really only need one tripod. When considering your budget, don't forget that you also have to buy the head. As Bill mentioned, there are two basic material varieties: aluminum and carbon fiber. There is a substantial price difference, but (personal opinion here) I think you only need carbon fiber if you're doing a lot of hiking where the weight reduction really becomes an issue.
Induro is the brand I use. They're nice without being terribly expensive.