The internet is a great place to look for bettering your career prospects. Whether it be looking at further education, or trying to find a new employer, the information is quite literally at your finger tips.
Taking a person looking for work in the insurance field as an example, there are several ways to do this. Firstly, they could just type in something like 'Insurance jobs' into a search engine. This may produce a list of agencies with positions available, but more likely than not, will instead produce a list of insurance companies actually selling insurance.
So, it is better to narrow down the search. Typing Hampshire jobs insurance, will narrow the engines search, and look for those three terms. This is most likely to produce a list of jobs available in Hampshire.
However, possibly the easiest way, is to simply search for employment agencies online. Making a list of a dozen of these sites could be a first step, and afterwards, searching them for specific jobs would be the next task.
Some companies will ask you to sign up, whilst others will let you search for free, but in order that you get details of a job, they will then ask you to sign up. If you do decide to, try and use an email address which is not your main one, as you will likely start receiving a lot of emails, even long after you have stopped using the sites!