As near as I can tell, JKR is either a closet slasher or she doesn't have a clue about teenagers…how many people's thought about their first kiss as 'wet'. My first kiss wasn't good, but it was sure as hell more memorable than that. Add in Harry alone in Snape's dungeons and Sirrius lying low at Lupin's and we have more subtext than you can shake a stick at. Besides, I know for a fact that one of the sites she recced had Sirimus slash pics on it.

As for the classic slash, I assure you that newbies find their way around rec pages and archives. It may take them some time, but they get there.