Right Emmy, you need to CHILL!!!!! You can be pencilled in before giving notice of getting married (or at least you can in Surrey Heath!). They get this all the time hun so will know exactly what you are talking about in your e-mail. Give them a few days then call them if no response.
Re the M&S wedding cake they do change their cakes regularly. How often I'm not sure, but the cakes that were around when I ordered mine are long gone, then when I got married they had just introduced a whole new set of cakes (Nov 2007), then when my SIL got married in 2009 they had more cakes then too I'm sure. They've recently changed all of their designs (bar a couple) so it's very possible that it might not be available still when it's time for you to get married (they only let you order something like 3 months in advance I believe). Try and gets of images so if you need someone to make it they have a good idea of what you want. Don't forget Waitrose do some great cakes! Check this out: Yellow Daisy Cake! Also, you could get a plain white tiered cake (M&S will ALWAYS keep this design) and decorate with sugarpaste flowers yourself? Here are some from eBay: daisies and daisy cake topper or blue & white mix with some coloured ribbons ad other decorations? You can order ages in advance as they last forever so can practice your designs, and are really cheap too.
And Thomas Cook are really struggling right now - there's talk about merging with Co-Op travel!!!
xxx