Tiny power supply: buy or make my own?

[TooFatGeorge]

I'm working on making a RF circuit that will replace a light switch (project log). It needs to be small enough to fit inside of a light switch enclosure. The digital electronics portion will be tiny, but I want to power it from the wall power (120V AC).

I could buy a power supply, but those are typically bulky. I am considering building my own so that it can fit in my desired form factor. I have a flexible voltage requirement (~3v-15v), and I'll be using very little current. I'm a programmer, not an electrician. I haven't studied power supplies in years. Do you guys have any tips on components I can use to build my own power supply? Or do you think I should buy a pre-made one?

 

[(*steve*)]

Have you seen mains powered USB chargers built into power points? The ones I've seen are tiny and should provide the power you require.

 

[TooFatGeorge]

oh brilliant! You have given me a new direction to google!