Originally posted by flockofbirds But I'm curious to where a good place to look for lenses would be? The pentax web store is pretty pricey as I would expect, but even looking elsewhere i haven't found the 55-200 under $200
First, make sure you are looking for the right lens. There is a 50-200 and a 55-300; there is no 55-200 (at least, not from Pentax). BTW, also note that if your P&S says it has a 135 "equivalent" lens, that means equivalent in film terms. to get the same figure for your DSLR, multiple the focal length by 1.5. So the 50-200 actually goes to the "equivalent" off 300 - way beyond what your P&S did.
As for where to buy lenses, the two most popular ptions would be Amazon - who actually deals with a number of different supplier, including Adorama, which is one of the major ones - and B&H Photo Video (bhphotovideo.com). Don't expect to see it *much* below $200, though - Amazon had it at $175 the other day, but it's back to $200 now. As I said, for years it sold for over $200, and it has only been very recently that one occasionally sees prices below $200.