Running

Barefoot running is one way of learning to run with a shorter stride and would avoid the need for expensive shoes.

+1 (though I use minimalist shoes rather than truly barefoot)

Also have a look at Sportpursuit.com. Sporadic sales of up to 65% off. Vivobarefoot and Vibram Fivefingers are often heavily discounted.

Downside is that you have to wait for the sale to finish for them to order from the suppliers, so delivery of up to a month isn't uncommon.

Vivobarefoot also run a free weekly running club in Hyde Park on Tuesday eves.

http://www.vivobarefoot.com/uk/community/?page_id=4235/

Run and Become in Victoria also have a lot of free workshops.