I've bought rope & gate handles through Paddock Perfection on ebay. Very good service & nice price! If you want the actual power unit I'd get a Rutland one. I bought mine from CWG so can't recommend online for that.
I have bought a few times from them and always great prices and delivery the next day. Have recommended them to friends and they have found them great as well. Very helpful staff as well who can offer advice.
not really 'online' as such, but i bought all mine for permanent elec fencing from Fieldguard, and have been really happy with it. it has stood up brilliantly to the mega-windy conditions here... a friend bought a cheaper type and had it professionally installed, and after 1 year in an exposed area every single connector had frayed the elec tape until it didn't carry any current... the whole lot had to be replaced.
if it's for temporary though, i wouldn't be so fussy!
yes ive spoken to them about things in the past and have just received my latest parcel from them of plastic fence posts and white tape - bargain. going to buy some more after payday lol (teaches me for running to the local agri merchant and having to settle for green tape - the girls didnt see it and ran through it in the night. must not do that again.
Fencing is a minefield, just make sure you get good UV stabilised posts! Recycled will be cheap,but is not correctly UV stabilised and will snap once out in the sun for a while. As for tape, the same applies, look for the best quantity of stainless steel strands woven into the tape, turbo tape or similar,with a wavy cross strand which re links the parallel strands is good, especially in windy areas. As for energisers, the Wolseley Mosquito is a great fencer, runs of a twelve volt battery and you can keep a six volt lantern battery in your glove compartment, so when you need to charge the big battery, you can use that temporarily and your fence will still be working.I am not a fan of buying fencing online, as there is so much cheap and nasty fencing kit out there, buy it from your local country store, at least you can see it and check out the quality.