Youve come to the right place brother and welcome aboard. Just ask around, post what you build, people on here are very helpful and just all around good people. Right now im mainly building big trucks, but im willing to help as much as possible.
My parents like yours thought my model building as playing with toys. Then i entered my 1st truck build in the county fair and took multiple 1st place ribbons, best ofs, and invited to the state fair. Thats when their attitudes changed, realizing this wasnt just toys, it was more, a passion. I took s break for about 10 years and got back into it, my drawers were just like yours, slim pickins, some paint, cheap brushes, no spare parts. But now, just about year back in to it, i have kits and parts and runnin out of room. Give it time, kit bashing will build your spare parts pile quickly, by kits just for rims or a motor or interior, next thing you know you have a stock pile. Happy building and again, dont be afraid to ask ?s or hey do have this part, youd be amazed how many will help