what to use as power source?

I've got a small pile of lighting projects for my 98 Protege, but I don't know what to use as power source. I tried replacing my trunk light with cold cathodes but now the fuse blows every time the trunk is opened (I gave up and replaced the bulb, I don't know why it still does it). The cathodes draw 5mA supposedly (that's what the box says) so I can't figure out why it would blow the fuse... How should I power them? I'm thinking I should build a fuse panel just for my additional accessories, run from the battery, but I don't know what kind of fuse to use for the cathodes (amperage).

The cold cathodes I've used are rated at 3 watts, which means the current draw will be 250mA. You may also want to put in a cheap voltage regulator as a friend of mine has somehow managed to melt the inverter that came with the CCFL. Something like this soldered to a stripboard will do: Voltage Regulator Make sure you put the fuse as close to the battery as possible.

Okay, thanks, but what rating of fuse should I use? And how can I make sure I don't blow the fuse?