hi coke,
ive had the same problem with those wirey stray grey aerial like blighters that keep popping up too! lol
a couple of weeks ago i decided id had enough of yanking them out and decided to buy a clairol semi permanent colour which lasts up to 24 washes, it was only �3.69 too! (from tesco)
i was very pleased with it, it took well and covered the sprouting grey excellently.
they offer a wide range of colours, and i think when i next have a go i might just choose a slightly lighter shade than this time, i have long dark honey blonde hair and it came out just a little bit darker than idve liked, but that soon righted itself after a few washes anyway, so no probs.
maybe give the clairol one a try?
i too was nervous about dying my hair for the first time, but was very pleased with it and it looks very natural.
good luck with what you decide, let us know! and have a great holiday! :o)