Only a small number of those are transformers, most are filters - the only one that looks like a transformer is the top right one.
I would
VERY much suggest you don't play with them, it's fairly hazardous and pretty complicated - as you can't seem to cope with simple basic battery powered multi-vibrators I would suggest SMPSU's are well beyond your abilities.
If you really, really, want to - then take the rest of the parts out of the circuit you got the transformer from, and re-build it. SMPSU transformers are custom made for every application, as far as I'm aware you can't just go out and buy them ready made.
You might also download datasheets for suitable IC's, here's a simple circuit from an old satellite receiver: