Good job so far
I can tell you what I did and no doubt others will give their advice
I got through the amateur level using the standard clubs without too much trouble. After that I bought credits and upgraded my clubs incrementally to what I have now at the Masters level. Some say you can get through the Pro level with the standard clubs but I personally was struggling so I upgraded. When you look into the Pro shop you will see many sets of clubs all with different attributes. Most will hit further, some give more feel, or more spin. Searching through the forums will give you information on how to choose. There are clubs for each level and the can only be played once you have reached that level.
A new putter is a given and either the Daytona which I have or the Redwood that a lot of others prefer are the best. Also there are many balls you can buy that have different attributes, distance, spin etc
Look through the forum to get ideas and read the stickys over here -->
It's impossible to give you all the info you need in one post so read through and get some ideas
Good luck
Mick