I have several manuals and use them all for reference. I would definitely get a book from the bullet company you mostly use. I use Hornady. I also use the Speer and Lyman manuals.
Public library may be a temporary source for you. Borrow or take a picture of the pages you need. Traildust here in Bloomington will let you reference what you need to look up while you are shopping for powder/projectiles.
The Lyman manual is one of the best for reloading procedures, plus it uses a variety of bullets and powders and covers all the popular calibers. Add one from your favorite bullet manufacturer and you will have a good start. If you use Hodgdon, IMR, or Winchester powders the current Hodgdon Annual manual, sold on newsstands, is a good buy. Accurate has a new manual if you use their powders. Happy reloading!
I have quite a few manuals and Sierra is by far the best in regards to instructions and considerations for loading. For data I would highly recommend buying more than one manual, because it help to see how different loads can be, for the same powder and bullet weight. The recommended charge weight range can be very different from manual to manual in some cases.
The answers above were all very good. Get many manuals. I like Lyman and ABC's of Reloading. The most important part of the manuals for beginners is the first half of the book. That contains detailed info on the reloading process. It is important to understand the processes involved and other concepts a beginner may not be aware of. Get several manuals and read the front part of each book before beginning reloading. You will have a better understanding and you will be much better prepared for loading your own ammo. I've been reloading for over 37 years and always recommend this for newer reloaders.
I like the Lyman's 50th edition, The ABC's of Reloading, and the Hornady manuals, but I also have a Speer, the Hodgdon manuals, one from Accurate...
You can never have too much information.
Using different manuals and searching the internet leads to madness. Many different manuals will have varied load data. Book for the weight and style bullet you are using is the best starting place. IMHO