List of general purpose transistors
I'd advise regular pin-through-hole devices in well known TO-92 (low power) and TO-220 (power) package. I think it is important to start with the knowledge where you left off. Sure, about 20 years ago we had SMD's, but a lot was still pin through hole. Above that, pin-through-hole devices are easy for breadboarding and as such to make a flying start. The devices below are cheap, easy to find and simple to use.

Bipolar

\begin{array}{ccc}
\text{Part}&amp;\text{Type}&amp;I_{C,max}&amp;h_{FE}
\\=====&amp;================&amp;=====&amp;=====
\\\text{BC547B}&amp;\text{general purpose NPN}&amp;\text{200mA}&amp;\text{200}
\\\text{BC557B}&amp;\text{general purpose PNP}&amp;\text{200mA}&amp;\text{200}
\\\text{BC337}&amp;\text{general purpose NPN}&amp;\text{800mA}&amp;\text{100}
\\\text{BC327}&amp;\text{general purpose PNP}&amp;\text{800mA}&amp;\text{100}
\\\text{BC517}&amp;\text{darlington NPN}&amp;\text{400mA}&amp;\text{30000}
\\\text{BC516}&amp;\text{darlington PNP}&amp;\text{400mA}&amp;\text{30000}
\\\text{BD139}&amp;\text{power NPN}&amp;\text{1000mA}&amp;\text{40}
\\\text{BD140}&amp;\text{power PNP}&amp;\text{1000mA}&amp;\text{40}
\end{array}

MOSFET

\begin{array}{ccc}
\text{Part}&amp;\text{Type}&amp;I_{D,max}&amp;R_{DS,on}
\\=====&amp;================&amp;=====&amp;=====
\\\text{BS170}&amp;\text{general purpose N-MOSFET}&amp;\text{500mA}&amp;1.2\Omega
\\\text{IRF520}&amp;\text{power N-MOSFET}&amp;\text{9.7A}&amp;200m\Omega
\\\text{IRF9520}&amp;\text{power P-MOSFET}&amp;\text{-6.8A}&amp;480m\Omega
\end{array}