A temperature controlled one is a good idea, as I've found that the ones without get too damn hot and end up damaging stuff. If you're just doing wires and sockets then it's not quite so critical. Also you can get away with a larger tip if it's just for wires and sockets.
I use a cheapo one from Craplins at the moment and it's doing ok for a £20 thing. Maplins don't sell them any more, but there's a chap in Stockport selling them on eBay for £15:
http://www.ebay.co.uk/itm/Variable-Temperature-Soldering-Station-Iron-Kit-NEW-/120730956097?_trksid=p2054897.l4275
Don't forget that if you're going for a new iron then you'll need to 'tin' the tip like this:
http://youtu.be/j1ZnkTC5bps
Also, when soldering offboard (generally wires) then you'll need to 'tin' the ends of the wires too - once you've stripped them twist all of the strands together and apply the iron and solder at the same time so that they turn a lovely, shiny silver colour - this stops any errant strands making contact with stuff that they shouldn't, and makes for a better solder joint.
Hope this helps.