Thanks, by 'any' pentax... even ,say, a twenty year old zoom lens?? As for what I want to do - some close up work, so some sort of macro lens?

Hi, I'm new to pentax cameras, but have taken the plunge and purchased a K-m DSLR with a kit lens. Now, I want to buy a zoom lens to go with it plus maybe a 50mm fixed... but don't know which ones would work (in automatic or manual) on the K-m... would ANY new or old pentax lens fit??!! Any help would be appreciated.