Hi,
I went to Ghana a couple of years as part of a village link with one in Norther Ghana.
Accra itself is much like England in many ways. It's fairly safe, has a good nightlife, bustling market(s) and some great heritage.
Kumasi is the central city many hours bus ride north. Be careful how you travel around.. there road fatality rate is horrendus. I guess your company will have laid on a private bus/car. They absolutely love football in Kumasi. If you get a chance to see a game then go.
Tamale is the northern capitol and where we stayed for most of the trip. It has a bustling market and some of the best mechanics in the world. I saw them repair a written off 52 seater coach over night using tools the aa would laugh at.
Outside of this area is the poorer villages we tried to help. It was a real shock to see people walikng miles each day to fetch stagnant water and women dying frequently in childbirth. Still, my grandfather is an honoury cheif and the reception and visiting the elders we recieved will stay with me for years.
Another good thing is the Mole game reserve. I think it has the largest collection of free elephants in the world. We were given tours and you get soo close to lots of beautiful creatures. It was really cheap to stay in the hotel and it's swimming pool is famous the world over.
Try and see the Volga dam, we never went that far east but i'd love to see it if i went back.
Generally Ghana is very safe and cheap, although expect to be ripped off if you are white, sad but true. Most people accept bartering. Accomodation is good and cheap, as is access to the internet.
There are very few snakes and other nasties around there, they don't like the soil very much.
All the best and pm me if you have any other questions
Charlie