I would imagine there would be a lack of people actually making saddles in the area, let alone taking on apprentices. You may find tack repairers and bridle/harness makers in the area but again, I'd doubt the volume of business would warrant an apprentice.
Walsall is obviously the place to go - our saddle makers have an apprentice - but otherwise you need to go via the SMS - either phone them and ask them, or locate all your local master saddlers and contact them directly.