This site - which you've probably already looked at - seems chock full of useful info re Guatemala City itself, especially if you scroll down: http://wikitravel.org/en/Guatemala_City
I nosed around a bit online and most sites seem to do with Antigua, Panajachel, Chi Chi, yadda yadda.
Lots of comments about G. City being dangerous. Uh. I don't remember that, but I've something of a high tolerance re what a lot of travelers think of as "bad", though I wasn't in-city very long and it was a long time ago.
Don't see a lot online re a variety of hotels, though most of the "usual suspects" are listed, re big chain types. There must be more...