Okay, we have built a great site on a local install (XP Pro machine with Express and DNN4.07).  It has a lot of content now, and we are ready to host it.  We just started the process to register the new domain name, and set up the extra account.  In a day or two, I am going to talk with them about getting our information FTP to them (new for me!).  How bad is the site going to be screwed up?  The only commercial module we are using right now is UMG, and I hope it works.  We are still evaluating commerce modules, and didn't want to choose one until the site is hosted.  Is this going to be a real pain in the rear getting the site transfered? 

I am sure I will have further questions over the next week, thanks in advance!

I just went thru this on a rather simple site but did have a few bumps along the way.   So here is a few other points to consider:

1) If you used the Responsitory module, you will need to update the path where the files are maintained.  You can get the absolute path from the Host Settings page once your file have been FTP to the site.

2) You will need to change your SMTP settings to meet the providers requirements.  -- spend a few minutes to ensure you have the information BEFORE you launch your site.

3) Create a app_offline.htm file so you can tell the world to "wait a bit" and also a good way to confirm you outside world can "see"  your  site.  When ready to let DNN run, simply remove the file (or rename).  Try it out on your test site to see how it works.

4) As soon as you have a working site -- back it up.  If you encounter trouble later, you have a baseline that works.

5) Take your time  and verify the results of each step before proceeding to the next.  Especially after FTPing file.  Sound simple but does really help. 

My site took about 8 hours on Saturday .. but I took my time and had to "fix" a problem I created that took a while -- it was an issue with SQL2000 vs SQL2005 that you will not encounter as you are using Express)

Good Luck.
Paul.