Hi Marky, I would agree with some of the above, but it's also about knowing the right places to look for marketing jobs. As you say, a lot of jobs claim to be marketing but are actually door-to-door sales or telemarketing.
Try looking on
http://jobs.brandrepublic.com/home/
and running a search. Alternatively, you could try enlisting the help of an agency (Hudson and Michael Page are big marketing recruitment agencies - although for something a bit more entry level, try Hays or Reed).
I've worked in marketing for the last ten years, I do have a degree but not in marketing. My route in was through taking a post-grad diploma in publishing which had a module in marketing, which like you, I enjoyed. I then took a job as a designer and editor for a classical music company before taking a marketing job for Which? magazines, specialising in the creative side. After a couple of different posts I now manage the whole marketing mix.
It helps to have a degree of some sort, as with many jobs these days, but it is possible to get there without one if you can build up enough experience and take a few marketing courses along the way.
Hope that helps, and good luck!