http://collab.kpsn.org/display/tc/TrinityCore+HomeI know nearly nothing about programming, using command line or SQL servers and still was able to compile my server on my own, on both windows and linux machines (linux via unix command line), so it is really simple. Just follow instructions for your OS and carefuly ready all of them before doing anything stupid, it will make all things much easier for you. Thats for your repack.
For races, I am not quite sure if you really know what displayID is. It is just a combination of model, some blood, sound and scale settings (for character models also items), which is all packed up in DBCs into 1 number you apply on NPC (or on player via .morph command [TC2]), however, it has absolutely nothing to do with creating custom race for players.
And, just btw, playercreateinfo table in world DB handles on which xyz coords, in which area on which map and with which orientation will be new characters of players created (northshire abbey for orcs etc). And that really has absolutely nothing to do with anything which leads to fact how players or NPCs look like. Google "playercreateinfo".