Builders in Chapel En Le Frith, United Kingdom

This may sound like a stupid suggestion, but try used furniture shops. If you can find old furniture in bad condition, they'll usually make a deal to get it out the door, you can saw it up and reuse the wood for other stuff. The wood in the furniture will be far less expensive than buying the equivalent wood new. Oftentimes the used furniture dealers don't know the difference between pine and oak and maple, they just want a profit, so if you do a bit of hunting you can find good stuff.

Whereabouts in South Wales are you? If you're near England, you could possibly get your stuff from some of the timber merchants in and around Bristol. I've bought from Robbins Timber (http://www.robbins.co.uk/pdf/Retail_Pricelist.pdf), who carry a decent selection of domestic and foreign hardwoods, and deliver nationwide. Eastman Timber (http://www.eastmantimber.co.uk/products.php) also do a bunch of hardwoods, although my only interaction with them has been getting quotes. You could also poke these guys, who look interesting and are on your side of the border: http://www.wentwoodtimbercentre.co.uk/

Try this http://www.exotichardwoodsukltd.com/ I think they have pretty awesome selection, alot of exotics!