User:Minimario
We recommend "Introduction to Number Theory" and the "Intermediate Books". They will help in current/future math competitions.
Links: http://bit.ly/mvsbtb http://amzn.to/jEuC97 http://amzn.to/jItP2v http://amzn.to/knwVjw http://amzn.to/mCQM6o http://www.amazon.com/Twenty-Mathcounts-Sprint-Round-Tests/dp/1456589148
AoPS