Hello Dude from that Place,
Probably the first step is to contact the Power company and find out what it will take to get the power lines buried.They probably will tell you that you will need to have the ditch dug and they will supply the cable and then you will probably have to have an electrician cut it over (customer side). Then once you have that information then call the phone and cable company and ask them if you can buried the lines in the same ditch. All companies have their own policies...Hopefully in your area the 3 companies will work with you so it doesn't cost a fortune....
Take Care,
Jim