With the publication of the AD&D 2nd Edition game, updating the original. Demigods are the least powerful deities of any pantheon. They are mortals who. Ture that will add flavor to campaigns in those mythos. Personal Entries.
I figure someone would appreciate this. As long as you have dice (which they sell sets at any hobby store), something to read pdfs, paper, and a place to sit you got a game. MODERATOR EDIT (5/30/2018): for those too lazy to go through this whole thread, most of the stuff in these links can be found at it's probably the largest collection of these materials on the internet. Click on scenarii TSR for modules. Every TSR manual is there their are some fan made ones here, their not too bad. Players handbook Moster manual Unearthed arcana another unearthed arcana book There is also Deities & Demigods and Fiend Folio but i can't find pdfs for them.
Honestly all you need is the players handbook, the first monster manual and the DMs guide and modules. Dm's guide and the second moster manual are the two attachments. My friend you are in for a treat! GURPS is some of the best worldbooks written, and the coolest system for Character Generation that lets you have nearly EVERYTHING you could want! 
Only so long as you stay within point-limits. I'll explain that later! It's Combat system can be good, or a pain depending on what you're doing. I find it works really good. If there's one downside to GURPS it's that the artwork covers/interiours usually suck! They've made some progress in recent years with the 4th edition, but still undermarketed, and thus they suffer.
Gimmie some time to locate some uploads for you all.