I use an older version of these
Ebay Wireless Triggers.
I have one sender and three receivers, each receiver has a
Hama Hot Shoe attached to it.
I replaced the pc-sync end with a
mono 1/4" jack socket from Maplins.
Total cost for the whole lot was about £20.00
For tabletop work I use a
Nikon AS-19 which can also be mounted on a light stand/tripod, cheaper options are available such as
this one if your flash gun does not come with one.
Biggest thing to remember for off camera flash is that you are not stuck with the expensive flashguns from your camera manufacturer, you just need ones that have full manual control over the settings. I use nikon SB-28 flashguns, I have 3 and paid about £40.00 each for them, they also just happen to work off the hotshoe of my camera - Fuji S2 Pro. I am too cheap to buy the SB-600 or SB-800 flashguns. If I ever upgrade my camera (would love a Nikon D700) I will have to buy one of the more expensive guns for use on the hot shoe.
For "studio" type work I bought my Umbrellas from ebay (can't remember who) 2 x silver, one white, all three from the same guy on ebay for under a fiver delivered.
If mounting flashguns on light stands with umbrellas, I use a
swivel mount.
Difficult bit is finding cheap light stands, all the really good deals seem to have stopped, mine are portaflash ones acquired from Tecno (owned by Jessops) before they sorted out the pricing (£5.00 from Tecno, £35.00 from Jessops)
Plenty more about cheap ebay triggers, and their uses can be found on the
Strobist forum.
This and the parent
Strobist website have all you could ever want to know about off camera flash.