Cheap Accountant has given some very good pointers.
Doing SEO yourself is always the best policy as you learn a new skill & obviously it saves you money, however, it is very time consuming, so you need to be able ot devote time & patience.
Also, backlinks are good, but if solely for SEO then only links with 'dofollow' links have any value.
Anyone know of any good accounting related sites that offer 'dofollow' back links?