An iWeb URL - which the index.html file at root level forwards to - always constists of
1. The domain name - http://electricaltradesmen.co.uk
2. The name of the folder containing the site - /Electrical-Tradesmen
3. The name of the actual page - /Home.html
It doesn't matter what you call the folder containing the site - it has to have a name even if it's only one letter - and it will appear as part 2 of the URL.
Roddy's workaround consists of publishing to a local folder, and then uploading not the contents of that folder, but the contents of the Electrical-Tradesemen folder - you can only do this by FTP-iing manually, you can't do it within iWeb's own FTP (assuming you're using that version anyway). This will remove the folder name but retain the page name, e.g. http://electricaltradesmen.co.uk/Home.html. Of course if you are FTP-ing manually you are going to have to upload the entire site and all its assets every time, whereas iWeb can upload just the changes (you could theoretically do that yourself, but I don't advise it).
There is another workaround, but it's a bit messy. You will have to create a different index.html file to place at root level. Open TextEdit IN PLAIN TEXT MODE and paste in the following code:
<HTML>
<HEAD>
<TITLE>Electrical Tradesmen</TITLE>
</HEAD>
<FRAMESET COLS="100%" BORDER=0 FRAMEBORDER=0>
<NOFRAMES><BODY>
<meta http-equiv="REFRESH" content="0; URL=Electrical-Tradesmen/Home.html">
</BODY>
</NOFRAMES>
<FRAME SRC="Electrical-Tradesmen/Home.html" NAME="Electrical Tradesmen" MARGINWIDTH=0 MARGINHEIGHT=0 FRAMEBORDER=0>
</FRAMESET>
</HTML>
Save it as index.html - don't let TextEdit ad .txt on the end.
Publish your site, then upload this file to root level, replacing the file which is already there. This should then retain the domain name alone as you navigate the site.
However, note that you will have to upload this file again after every single time you publish your site as iWeb will overwrite it. You can get round that, but it involves republishing the entire site inside another folder, and amending the URLs above to include that folder. This would mean that the 'real' URL of the Home Page would be http://electricaltradesmen.co.uk/Newfolder/Electrical-Tradesmen/Home.html but entering the domain name alone would work as before, and you wouldn't have to keep reuploading the root level index.html file.