dvd.co.uk is selling the expansion pack for one the best games in 2005 for only £9.99 (delivered). Cheapest I can see elsewhere is 15-20£. You can get 5% Quidco on this if you'd like to.
In case you don't have F.E.A.R yet (required), you can also get it for £9.99 at the following URL: dvd.co.uk/product.asp?id=VU95882.
The F.E.A.R. expansion begins where F.E.A.R. left off. The game starts immediately after the player's escape helicopter crashes as a result of the blast that signified the end of F.E.A.R.
With new weapons and new grenades, the player will have to fight off some familiar foes as well as some new ones. The expansion will continue to build upon the close quarter combat and paranormal horror moments that made F.E.A.R. what it is.