http://www.dogcages.net/features.htmMost of the larger firms are very expensive and their lead times quite long if it is a custom made jobbie.
Barnesbrook are of very high quality, designed and made by an ex aircraft engineer, and much less expensive than some other well known makes. They are also silent! :D
I bought mine after seeing several examples of his work and it is superb; I am familiar with all the makes in the UK and IMHO this firm is the best. He will also put on little extras for you such as leads for hooks etc. I cannot recommend him highly enough.