Disclaimer: My business is located in Denmark, but I don't see why that should matter much.
I am getting about 80% of my new business via my web site. The vast majority (90%) locates me via Google searches.
At least half the business is generated via adword ads, the remainder via normal ("organic") Google search results.
I have stopped using classified ads in the local papers, since the payback on the investment was far lower than using Google Adwords.
The business that is being generated equals approx 1½ full-time employment (not counting jan/feb 2010 )
I should say that I have a background in the IT business, and have spent a lot of time optimising (SEO = search Engine Optimisation) the site and playing around with adword ads.
If you are not desperate to get you business kickstarted immediately, I suggest you try out generating your own site with only a few pages.
Start out with the free website offer detailed in this thread http://arbtalk.co.uk/forum/general-chat/14559-free-web-site.html
The site that backs this offer is hosted by Google sites.google.com, easy to work with and easily optimized
Then start playing around with Google Adwords and Google Analytics (visitor statistics), and read som SEO guides to work on your Google rating. Google has a brilliant SEO guide here: Search Engine Optimization (SEO) - Webmaster Tools Help
If you find the DIY approach too daunting, or you want your website to have an effect quickly and you have some money to invest (I guess £200 - £500 would get you going), I suggest you get someone to create a website for you, and do the SEO too. But watch out, there are a lot of fraudsters around. Do a little market research before committing to spending anything. Get references, and talk to their other clients about their experiences.
Another approach would be to search google for...
ARBORIST KENT
... or similar search terms, and have a look at top-10 search results, and find out who created those sites - they generate business. Also check the AdWords ads that are shown at the top and right hand side, and see which ones you believe will generate business. Let yourself be inspired by your competitors, but DO NOT COPY! Don't even copy a single sentence or adword ad. It is illegal (copyright infringement), and you might end up in court paying top £'s. Just take my word for it!
Remember to limit the Adword Ads to the geographic area that you cover. No point in paying for AdWord clicks from Scotland.
Hope you can use the advice.
Good luck.
Morten