The workshop will be held in July, so it'll presumably be hot and humid; expect daily highs somewhere between 80 and 95. However, the computer lab (where we'll spend eight hours a day) is air-conditioned, so you may want to bring long-sleeved shirts or even a sweater. It may well rain, so bring an umbrella.
We'll be holding the workshop in Swirbul 202 (a classroom) and Swirbul 101 (a computer lab). The computer lab is all-Windows. The software runs equally well on Unix, Windows, and Macintosh. You may bring a laptop (Windows, Macintosh, Linux, whatever) if you wish, and install the software on that -- indeed, if you want to install it before you arrive, it's available for free download.
We'll provide textbooks. If you want to get a preview before you arrive, the main textbook I'll use is my own, which is free on the Web, as are some of the other related books. You don't need to bring other Scheme texts or references; this course is self-contained.