Pop into your nearest STA travel and have a chat with the staff. They are very knowledgable and helfull.
There are lots of organised tours you can do. One of my friends (a 32 year old female) has recently done a 6 week tour of Thailand, Laos, Camdobia and Vietnam with a group of people who she had never met before. She had a fantastic time and is now in New Zealand / Oz travelling around there on her own.
I went travelling with my girlfriend for a year and we did Cook islands, Fiji, New Zealand, Australia, Singapore, Malaysia and Thailand and it was the best experience we have ever had. We met so many nice people, young and old, English and foreign, locals and other travellers. If I had the money I would do it again at the drop of a hat.
The flights were about �1,100 each. Get down the library and read up the lonely planet guides which are perfect for travelling.
Go for it!
(feel free to ask any questions you like)