I have to add, since I did a control bomb last Sunday in my room, I havn't seen a single spider... I have looked around a little and have kept an eye out and have come across nothing...
It could easily be coincidence, but considering how often I saw them before I did the bomb, and that there has also been a heat wave here since christmas, their should definetly have been more around...

So I have to give 2 thumbs up to the use of the bug bomb... The instructions said to use one per average size room.My room is a little larger than average, but I still only used one. It came in packs of 3 so I thought i'll use one, clean up all my crap, and then do another or 2 after that if it was still needed.. .But as I havn't seen any spiders since, 1 may have done the job.

They were also very convenient. You just stick it on a newspaper in the middle of the room, shut all the doors, wait 2 to 3 hours, then open up the doors and air out the room for half an hour... After that it was perfectly livable.. Their was a hint of like, fly spray smell, but just enough to remind me I didn't have to live in fear anymore, so it was welcomed. Far from having to put a tent over your house and go on holiday for a week

Anyway, here is a link for the bombs I used:
http://www.mortein.com.au/product_flea_plus.php

It's an Australian company, but i'm sure you can find similar.
The active ingredients were "Permethrin" & "Fenoxycarb". On a spider website it said that fenoxycarb was the most effective chemical that a regular person would find in a regular shopping centre to get rid of white tails.

I also bought these 2 surface sprays for inside and outside :
http://www.mortein.com.au/products.php

I did around the doors and windows and in between any gaps in the brickwork with the outside one. I havn't used the inside one yet, but may do around the doors, windows, behind cupboards and around the edge of the carpets on the inside when I have some spare time..

Finally I bought an all purpose spray to kill any spiders on site :

http://www.mortein.com.au/product_roach_lure_spray.php

My only problem with all of them was, they have a big picture of a cochroach on the front and all over the product they talk about how they are amazing at keeping away fleas and all these other insects, but only mention the word 'spiders' once.... So I was totally convinced I would completely eliminate ANY roach or flea problem I had (which I didn't), but not very convinced that the products were made very specifically for spiders.

BUT, so far i've been completely happy....

and since the purchase,,,, Me 1, Spiders 0.

I also saw another product advertised which is a small electrical device that you plug into the powerpoint, and it sends out electrical signals in a circle which spiders and insects hate and won't come near... I think someone mentioned it earlier and it sounds like a great thing, but I would do some research first and see if it's been tested and proven to work effectively in a house. They may have been able to stick it in a box with a spider and the spider didn't like it and tried to run, but it may not work so well over a whole house through walls.