Oh god, you are so better off without this peice of scum.
Right - debt i can help with (way too much experience :( )
Firstly - you can get a half hour consultation with a solicitor: You need to make a list of things to ask so that you get what you need answered, the lovely ladies on here will help you with that.
Court summons for council tax is quite early in the line of events - they send these out quite freely, CALL THEM, tell them that your husband has left and they will advise you on what to do.
The electricity can't be cut off if you have young children - again, talk to them, the electricity company wont tell you this but there is an organisation that can help, i can't remember who they are off the top of my head but you can basically write to them with your circumstances and they can help towards the bill. If you contact the national debt line, they will advise you about this. Volunteer (don't let them force your hand so ask before they do this) to have a key meter installed - absolutely the best thing we ever did, for the gas too. You pay a tiny amount more (this does depend on the company though) and can put your debts on the meter so it takes a little extra each week - we had to battle but we got ours down to £12 a month for a £700 bill for the gas and £5 a month for the electric. This is far better than getting huge bills.
Write to all your creditors - tell them what has happened, offer token payments - by token i mean £1 a month, this means they are much more reluctant to take any court action as the court is likely to find in your favour - i have done this, for most creditors this works, we had one set of cunts that woudlnt accept and wanted a ridiculous amoutn of money, tried to intimidate us, court found in our favour - you just have to arm yourself with your rights. Again, the national debtline can help with this, their website is fab and has template letters etc.
Make sure that any creditors for debts in your DH name know that he no longer lives there and pass on his details. If it gets to the stage where the bailifs come (sorry but this could happen if he defaults and doesn't contact creditors) YOU DO NOT HAVE TO LET THEM IN, in fact, you must not - they cannot take anything until they have made note of it, and they can't do that without entry - just tell him your DHs new address and shut the door. If they persist, call the police. Hopefully you wont have to deal with this though.
Sorry this is long and possibly not what you need just now but when you look back over this thread you might find some snippets that are useful.
Its time to get angry!!