Hi Martin, and firstly welcome!
Before going on to suggest an alternative to ISEB course, can I ask why you are looking for such a course?
My suggestion for an alternative would be the online distance learning modular programme we have developed at www.smart-BA.com - you get use your own project as the case study and work with your own mentor through the modules at your own pace, graduating with a way of working that you know works because you have completed the analysis of your project, and you have a set of analysis templates that you may want to re-use...
The main focus of this programme is on doing analysis, not just learning about it, and you do it on your own work, not some artifical case study, and you work one to one with an experienced Business Analyst, not just be one of a crowd in a classroom.
I hope this helps - let me know what you think via these forums or Guy@smart-BA.com
Guy