Making it yourself is good but I guess it would be way costlier than $3.00 ones.
Regarding BJTs, I have these in my toolbox:
2N3903/2N3904 (NPN) & 293905/2N3906 (PNP) – General Purpose Transistor
2N222A (NPN) – General Purpose transistor
BC547 (NPN) & BC557 (PNP) – General Purpose transistor
TIP120/ TIP121/TIP122 (NPN) & TIP125/TIP126/TIP127 (PNP) – High Power Darlington transistors
BC517 (NPN) – Darlington Transistor
TIP31C (NPN) & TIP32C (PNP) – Power Transistors
BD139 (NPN) & BD140 (PNP) – Medium Power Transistors