For advanced handloading I agree with Quickload software. Pricey but the best investment I ever made in reloading. I have 2-3 editions of several manuals and QL is always within reasonable range of them and gives loads for many unlisted combinations and good velocity estimates for various bbl lengths.
Lee is good for discussion of pressures, Sierra is one of the advanced basic manuals. If you are going fir reL precision then get those kind of books that go into concentricity, etc. For general reloading I think the next step up us a chronograph and QuickLoad.