I'm interested in putting together an AR-15 someday and the site will probably be invaluable to me then
Yep, the tech forums are a great help. As are the for sale forums, with links (and sometimes sales and deals) from all the manufacturers.
But as mentioned, the general forum is pretty much a waste of bandwidth. Breaks down into an 'I'm better than you' fest, with few moderators. The minefield on gunboards is tamer than this place on occasions.