In my local Asda (Gateshead next to Metrocentre) they have loads of gardening items reduced. Pick of the bunch has to be spades from £1.50.
The £1.50 ones were made of Carbon Steel but they also had some stainless steel ones which seemed a bit more sturdy and were reduced from £12 down to £6 and now down to £3 so I picked one up.
I've looked online but don't seem to be able to find any garden spades on the ASDA site.
Can't go wrong at those prices:)