Recently started playing again and am completely lost to all the different abbreviations people are using. Is there a list on site or somewhere else that has a list of commonly used abbreviations/acronyms?
Not far as I know, but quite a few handbooks explain the acronyms they use. Most of the acronyms refer to various books, so getting reacquianted with the full names of those can help quite a bit. SpC refers to Spell Compendium and pretty much all the acronyms starting with a C refer to a book of the Complete series, for example. I typed down a brief list of book acronyms to the spoiler below, hopefully that'll give you an idea how the system works in general.
- PHB=Player's Handbook
- PHB II=Player's Handbook II
- MM I-V=Monster Manual I-V
- CAdv/Arc/C/Div/M/P/W=Complete Adventurer/Arcane/Champion/Divine/Mage/Psionic/Warrior
- BoED=Book of Exalted Deeds
- DMG=Dungeon Master's Guide
- MIC=Magic Item Compendium
- SS=Savage Species
- ToB=Tome of Battle
- UA=Unearthed Arcana