I'd recommend getting the Lee manual. The Speer book only has loads for Speer bullets, and that's quite limited information in some calibers. Also, the Lee book will give you some background on their philosophy on reloading and why their presses and equipment are built the way they are.
Another good manual is the Lyman. It lists powders and bullets without restricting to vendor, and it a pretty complete guide. Hornady has a good set of loads in their manual as well, though they're going to be specific only to Hornady bullets. Fortunately, they include enough generic (FMJ & lead bullets) bullets in their lineup, that the loads are generally interchangeable with bullets of the same type and weight.
Generally, here's how it works:
Equipment manufacturers (Lyman, Lee, RCBS, etc) will give you *more* complete listings of powders and bullet types in their load data.
Bullet manufacturers (Speer, Sierra, Hornady, etc) will only give you loads for their specific bullets. Some have a broader range of powders (Hornady is a good example in most calibers), but bullets may be very specific (Sierra, for example) and not translatable to other bullets for OAL measurements.
The best advice is to get as many sources for data as you can, and use a conservative starting point. Also, don't forget to check with the powder manufacturers, as their websites often have useful load data. Here are some:
IMR/Winchester/Hodgdon:
http://data.hodgdon.com/main_menu.asp" onclick="window.open(this.href);return false;
Alliant:
http://www.alliantpowder.com/reloaders/default.aspx" onclick="window.open(this.href);return false;
Accurate:
http://www.accuratepowder.com/reloading.htm" onclick="window.open(this.href);return false;
(this is a PDF, there's not an interactive online guide)
Ramshot:
http://www.ramshot.com/powders/loadguid ... 0V4.3b.pdf" onclick="window.open(this.href);return false;
(another PDF, no online guide)
Vihtavuori:
http://www.lapua.com/index.php?id=1180" onclick="window.open(this.href);return false;
There are also several online resources for data, if you're having a hard time finding a load for your particular powder/bullet/caliber combination. I have found hanloads.com to be a good resource:
http://handloads.com/loaddata/default.asp" onclick="window.open(this.href);return false;