I posted this in the Weddings forum but maybe it would better fit here.

So I've decided on the dimmable 35 watt Cool Lux with a soft box to light receptions, but what kind of power should I get? Battery belts, fanny packs, shoulder packs? What lasts the longest? Someone help me, please.

I apologize, I'm new here.

Mark I answered that for you in your original post in the wedding forum. Please don't cross post as it makes it very difficult for anyone to really help you out.
If you want someone to tell you exactly what to get we can't. It's your money but if you take the information given you then have the information needed to make a decision based on real world experience using the equipment you are looking to purchase.
If you want the longest runtime possible then get a battery belt-if you can do with shorter times then get a juice box or shoulder carry battery. Lead acid is the least expensive but heaviest, NICAD more expensive but lighter.
The choice is yours.

Don

Thanks for setting me straight Mr. Bloom.