I think it'll be difficult to get into some traditional entry level marketing jobs as they often require a degree, however that shouldn't put you off.
Marketing covers such a huge array of disciplines - from Product or Brand Management to working in an advertising agency or PR company.

Starting salaries in Marketing probably range from 15-25k depending where in the country you work and how big the company is.

Work experience is often a good way into Marketing so try to secure some for the end of your course. If your college has a careers department ask them if they have any links to local businesses which may offer this.

Monster is great for Marketing jobs www.monster.com

Marketing Week is a good place to learn about the industry
- http://www.marketingweek.co.uk/

Also so worth contacting a few recruiters about entry level marketing jobs. Try - http://www.everyrecruiter.co.uk/marketing

Good Luck