Included with his gear is the SPEER Reloading Manual Number 10.
A quick Google search shows that manual may date from 1981 -- so it could be up to 35 years old.
I believe that old load data is still valid. I don't think powder formulations change over time, so load data from 1981 should still be usable today as long as you can find powder with exactly the same name.
Make sure that the modern powder you buy is EXACTLY what is called for in the manual. Many powders have similar names, so check and double check.
I bet that if you compare the loads in the old manual to loads in current manuals you'll find that the current loads are lighter. I suspect that's due to legal and liability reasons.
Personally, I'm not sure I would use a manual that old for general reloading. I'd use it to research loads for obscure rounds -- there are probably a few cartridges in the 1981 manual that are no longer included in modern manuals. And I would compare the loads in the old manual to modern loads just out of interest. But I don't think I would take the old manual as gospel.
As for current manuals, I'll echo what everyone else seems to be saying.
There is no one best manual and you will likely get many manuals over time.
The Lyman 49th Reloading Handbook is a good general refernce. I started with that myself.
If you use a particular manufacturer's bullets a lot, get their handbook. I use the Hornady 9th Edition because I mostly load Hornady bullets. I've looked through others -- mostly the Speer manual -- but do not load their bullets often enough to invest in their manual.
The Lee 2nd Edition is a good general reference and I think it is the least expensive of all of them.
The Hodgdon Reloading site at
http://www.hodgdonreloading.com/ is very handy.
The Lyman Cast Bullet Handbook is good for cast bullets should you ever get into that.