I want credit!

Hello all!
Heres my short story :) About 10 years ago i made bad choices ofcourse. I was 18 years old and i got a couple of credit cards and joined gyms and cell phone plans etc. My debt wasnt that bad but my credit score is about 500 i believe.
I had an ex girlfriend whos name was also in the mix of it all so i spoke to a family loan shark friend who lend me 10 grand or so. I spread it out and paid the most creditors i could. Yesterday! finally i finished paying the loan shark! im extremely happy about that. i was paying $125 a week all these years.
Im 27 now i have a son and although i have a great job i still need credit for an apartment and many other things in life! Many jobs are also checking your credit score. The problem is that many of these creditors stoped sending me mail i just know that i owe bally total fitness about 2 grand also a cell phone company about $900 who i believe went bankrupt but i was still getting mail years after they went under.
There may be more i dont know about but i just wish i can get em together pay em off and start getting credit! Also i dont think ive been sued i havnt seen anything. Thank you!