Do you have any training programs in your country? Have you participated in any other contests? If you haven't, AoPS has a lot of useful resources. Once I'm home, I can send you a pretty big Dropbox with a bunch of material but most of that is more advanced. If you're just starting out, I recommend (apart from seminars and participation in training programs) that you read a book like Engels Problem solving strategies and work through the problems
Edit: I realize your 92-93 likely refers to some practice tests rather than school math. Most of what I said is probably moot then, but I can still send you the Dropbox and some other resources
