Christmas Positions are always a good way to get retail jobs which will give you more experience and make you more employable.
Hospitality is also a good place to gain experience, Most restaurants and some bars (Wetherspoons) will employ people without a lot of experience as they often prefer someone who has not picked up bad habits.
supermarkets are also a good place to gain work experience, you could also ask at your local careers center. They will often set you up with a weeks work experience which is ideal if you want to gain experience in an office environment.