This often cannot be easy considering the fierce competition in the sector, you'll find yourself inundated with deals right, left and centre. The best way to narrow it down is to ask yourself a few simple questions:

How much do I want to spend?

What functionality do I require?

Do I already have a graphics design who will design the layout?

If you have strong corporate branding designed by a specific graphics designer it's probably best to stay with them for the site in order to maintain continuity. The functionality that you require on your site really narrows down your options when it comes to designers/developers for example is your site going to be static or dynamic? If you require a dynamic site it's best to go with a developer and if you would like a static site it's probably best to go with a designer. Most developers/designers have a specialty and it really pays to search around to find the right developer/designer best suited to what you would like done.

When you ask yourself how much you want to spend remind yourself that a website isn't like brochures, you don't need a complete redesign for each product your offer. Although I do recommend that you give your site a fresh look every year or so (subtle colour changes, different content on the front page). A website is a worthwhile investment to any business so be prepared to spend good money on it. The extra money spent will definitely show in quality.

So by now you should've narrowed the list down significantly, I now recommend you ask the designers a few very important questions. The first one is what language they code in. The current standard for websites is XHTML 1.1, if your web designer is unsure or can't give you a clear answer it's probably not a good idea to use them as they don't understand the fundamentals of web design. Many web designers use graphical tools to create websites (such as dreamweaver) which is ok to do but you must ensure they "clean up" their code afterwards you must also enquire about what browsers they check your site in. All web browsers interpret code differently and if your web designer only checks in IE for instance you could be missing out on a lot of potential mac/linux customers. Look at examples of your web designers work and search for the sites in Google to check whether they have done a good job with SEO (search engine optimization), If they haven't don't dismiss them as you might be better off going with a company that specialises in SEO after your website has been built. Make sure you like their style and also ask them about how much JavaScript they use. Web designers who use a lot of JavaScript instead of css/server side technologies generally produce poor quality sites in comparison as JavaScript is considered an annoyance among much of the web community.

Obtain lots of quotes and if you see a quote that is a lot different than all the others ask them why also ensure you get a clear idea of how much updates will cost you as this is a very important factor if you update your website regularly. You may find that they hand code all of their sites (which is quite good because it means that they have a good understanding of coding). It's also a good idea to go with a web designer that offers their own hosting service. This is especially important with dynamic sites as getting your own hosting, which may be a lot cheaper initially will start to cost you if you have problems as communication with the 3 parties involved (you, your web designer and hosting company) could cost you valuable time.

Choosing the right web designer/developer is a complex process but is something that you should devote some time to because there is a world of difference between one web designer and the next.