Usually the most productive websites are the simplest to navigate and find what your looking for, one thing I see in alot of photography websites, is the photographers/webdesigner allows their ego to override their purpose, to often we see websites where the skill of the programer outweigh the skills of the photographer, myself personally don't like flash, frames or to many things on a page competing for my attention, if photography is the focus, make sure the photography is what stands out, and not the technology of the computer..
One of the most important things to have a successful website, is the promotion aspect, you can have the prettiest website, if it is not promoted correctly, then it is a waste of time, this means making sure titles are in the page, key words and key phrased are properly done, text is spelled correctly, scrolling side to side, is ususally a no no, unless for panoramic prints, make sure your pictures don't take to long to load, I try to keep images under 100K, a big no no in website design is ever having the term "Under Construction" anywhere on the website, most search engines will not visit again if they run into those terms, so when you submit to search engines make sure it is ready for public viewing, make sure it is easy to contact you either by copyright on the bottom of the page, or have a dedicated contact page.
In other words, don't do anything that makes it complicated for the prospective client to buy or gain more information from you.
Dave