daredevil123 merely mentioned that Pentax makes a lot of lenses, some very famous (and also expensive too)... He didn't say Pentax lenses cost more than say... Olympus lenses (which you'll need if you get an interchangeable lens camera like EP-1 or EP-2).
Don't confuse the facts.
In fact Pentax K-x with kit lens already very capable. If you don't want to buy additional lenses, that's fine too!