So I have been dealing with the same thing and here is what I have found out so far.
1. It has nothing to do with this theme. I have tried several including the default and the speed is not changed.
2. The slowness is primarily when you first hit the site.
3. WP Super Cache did help dramatically for the slowness going to new pages/posts after already on my site but did not seem to effect the initial page load.
4. General WP.org forum shows many godaddy users complaining of slowness with WP but no solutions really.
5. I have an open support ticket with GD backline and they have no clue what is going on. Had me add cache but ultimately telling me it is not their fault.
I am not sure how that might help you but at least you might save time not chasing as many dead ends as I have. There is something wrong with how GD works with WP is the bottom line and I have no clue what it might be still.
If you want to see for yourself, just go through this forum and every time someone gives a link to their blog click it... you will wait up to 20 seconds for the page to load. We have to be losing major traffic!!!
Anyone found any solutions? My site is http://www.inspirationalparenting.com