Yahoo! has a handy page (http://developer.yahoo.com/performance/) with lots of good info. It includes YSlow (a Firefox add-on), a set of "Best Practices," and some good research. Also references a couple of O'Reilly books (which, to be fair, I haven't read).
More specifically, CSS sprites (see http://www.alistapart.com/articles/sprites/) and consolidating Javascript may be back (reducing HTTP requests), and a few other things that may surprise or inform.
Buy the Home Despot or Black & Decker book, learn some new skills. You will save a ton, and can use those skills next time around. (Words of warning: read the explanations first, especially for plumbing and electrical, and check into permits/inspections. And draw good diagrams -- it'll pay off handsomely in short order.)
Math is like love -- a simple idea but it can get complicated. -- R. Drabek