Hi Deanski,
In response to your first question, I'd start out by giving your Excel a run for about two hours with just charcoal and wood in there, no food. After that she'll be good to go. There will be an improvement in her behaviour over the fisrt ten or so cooks as the seasoning builds up and the seals around the stackers improve.
As for smoking woods, my first suggestion would be to email Paul at
http://www.smokingwoodsupplies.co.uk. We get all our wood from Paul and he is a top bloke. Prices are reasonable for good sized chunks, if you're local to him you'll be able to collect but if not then he will ship out to you. Shipping adds a bit to the cost but his prices are very sensible.
I'd recommend starting out with some oak and some cherry, or maybe some apple. I find that apple is generally easier to come across for free than the other woods, at least once a year I have friends who are cutting back an apple tree and apple also works well when it's still green which is an added bonus.