I'm perpetually skint so here are some moneysaving tips:
I'd recommend joining your local freecycle, we had the majority of our nursery items for free: oak cot and changing unit, wardrobes, highchair, and loads of other stuff too numerous to mention. Means you can get rid of all the baby crap which soon accumulates too. I got an avent steam steriliser off freecycle but if you're intending to bf you probably won't need a heavy duty one so you could get away with buyng a travel steriliser from tesco for £5, or 3 resuable steriliser bags (20 uses from each one) for £4.
Mine's not here yet but I can tell you some of my best buys so far:
£6 hospital bag from barratts
£25 graco travel system from ebay
£8 tummytub from ebay
£3 changing mat from wilkinsons
£4 baby gym from a carboot sale (still on sale in shops at £50, and was immaculate)
£5 battery operated vibrating musical baby swing from carboot
£18 freedom sling from ebay
I have bought far too many clothes though, I have MASSES of newborn outfits/0-3 months outfits, I'm hoping he won't be massive cos it'll be such a shame. Wash half the clothes and leave the tags on the rest as much as possible, either take them back or if they won't have them back cos it's been too long, sell them in bundles on ebay. Brand New With Tag (bnwt) clothes sell for more.
Oh and if you're having a girl, be aware that the more frills on the clothes the more time consuming they are to iron, and you will have to iron them!
Before the event stock up on nappies (but not tiny size, you can guarantee at some point he will be 6-13lbs) just get one or two packs of newborn size, you can always buy more when you know how big he is. Also stock up on washing powder, loo rolls, toothbrush, all the basics you'll definitely use so you don't have to do massive shops, make it as easy on yourself as you can (I just spent a fortnight making meals to freeze for after the birth, dp is now munching his way through them)
Haven't bought a breastpump, but if you are going to get one, ebay has loads of nearly new ones because some people try them and decide it's too much hassle or they don't need one, or go onto formula. You can expect to pay around £20-£25 (less than half the price in mothercare) for an electric medela breastpump if you're quick on the mark, but they get snapped up quickly!