How to Identify Recruitment and Headhunting Firms

There is a fairly comprehensive list of UK-based Executive Search firms, specialising in the Asset Management Sector, on the Resources area within Godliman’s web site, which you can download here .
You can find more firms from the following resources:
The Executive Grapevine:
This is a directory of all the recruitment firms in the UK (and, less comprehensively, globally). You can select firms by sector coverage, and by category: ie: Retained Search, Agency or Selection. The City Business Library in the Guildhall used to keep a paper copy of the directory, which you can access for free if you ask the librarian.
The AESC:
This is a web site run by the Association of Executive Search Consultants, and lists their members in the UK.
Google:
If you perform the following searches:
“Asset Management” Executive Search site:uk                           or
“Investment Management” Executive Search site:uk
or variants thereof, you will tend to get a decent list of Search firms; though watch out: you will also get Agencies presenting themselves as search firms;
You can also try:
“Asset Management” headhunters site:uk
If you use the word “Recruitment”, you will get mainly Agency Headhunters.
Selection web sites:
Since Agencies often combine Agency recruitment with Selection recruitment, another was to identify relevant Agencies to look at Job Adverts on sites like LinkedIn, e-FinancialCareers, The FT, and Albourne Village, and search for jobs in the field in which you would like to work. Then, make a note of the Headhunter managing the advert responses: even if that particular job may not be an exact fit, it at least means the headhunter works in a relevant area.