http://www.joomlaos.de/
This is a German site but easy enough to use. It has over 1400 templates available for download (in the category 'Templates for Joomla and Mambo 4.5.1). The templates are displayed in gallery format and immediate preview is available on each. The only irritating aspect of this website is that for protection against bots they have implemented a system to constantly check if you are human. Depending on the type of access that you have to the Internet you may or may not be bugged by this.

http://www.mambohut.com/
This used to be one of my favourite sites for Mambo and Joomla templates. Sadly, their gallery is not operational at the moment. The only way to look at the templates is to select the 'Template preview' option. After you've selected your template, you can search for it in the downloads section and download it. Clunky!

http://www.joomlahacks.com/joomla/templates/0,0,0,0,6,0,8/
Joomla Hacks has a collection of about 226 templates, displayed through a gallery. You need to be registered to download.

http://www.joomlaresource.com/joomla_downloads/
Download/Joomla_Templates/
They have about 170 templates also displayed in gallery format. You also need to be registered to be able to download.

Commercial Joomla templates

There are numerous websites available with commercial Joomla templates - most of these offer great designs for very reasonable prices.

My favourite sites for commercial templates are (in no particular order):

http://www.rockettheme.com/
These templates are characterized by being on the cutting edge of web design. Their latest designs are 'Web 2.0' oriented but all their designs are simply stunning. They do not sell templates individually but through a membership (template club) scheme. The club membership does not allow you unlimited usage of their templates, but restricts you to how many templates you can use concurrently. For example, for $50 you can use 2 templates out of their collection.

http://www.the-template-shop.com/
Very stylish designs, each of which come with a variey of headers and colour schemes, making them very tailorable. They are sold individually for about 30EUR each.

http://www.compassdesigns.net/ and  http://www.joomlashack.com/
These two sites are affiliated and you will find the same templates on both. A small selection of templates, but high quality. Templates start at around $36 and can be bought individually.

http://www.pixelsparadise.com/
These templates are 'nice' in a straightforward kind of way. Sold individually for about 25EUR each.

http://www.joomlart.com/
Some of their templates don't appeal to me, others are really nice. They also don't sell their templates individually but through a template club. Depending on the type of membership option that you take, you can use their templates on either 1 domain, 2 domains or up to unlimited domains.  Frankly, I think that the term 'Membership' is a bit of a misnomer seeing that you are basically locked into using one template on one domain at $40 for the '1 domain' option. In effect you are buying one template for $40. 

http://www.pixelthemes.com/Buy-Joomla-Templates/Affordable-Cheap.html
A small collection of templates at reasonable prices. They don't have a proper gallery layout for viewing their templates - which I think is a drawback.

http://www.joomlajunkie.com 
Also a relatively small collection, but nicely laid out with online demos. They pride themselves in 'colourful' templates!

http://www.joomladesigns.co.uk/
This is my favourite of all the commercial template sites! Extremely good value for money at 25EUR for a year's membership, unlimited usage of the over 200 templates. They have a very nice flash template gallery. Be warned though, of two things - some of their templates are quite repetitive, you can see it is the same template just with different colours and headers, and some of their older templates are not that well designed internally (I found one making use of <font> tags! Eeek). But apart from that, good value for money!  

Tags: Joomla Templates