Having your own web site is a must. However, it will not get you instant results. Its a labour of love or an investment for the future. Also, its only part of the marketing picture. Our site on Orlando Vacation Rental Homes is a good example. I get between 40 and 100 visitors per day but it has taken me 18 months to get that amount of traffic from organic search (as opposed to web advertising).
For me, the most important things are:
1. Get a good site with pages optimised for your market.
2. Promote your web site - get links from other sites on the same theme (see above for the correct way to put in a link for the keywords "Orlando Vacation Rental Homes")
3. There are many ways of doing this and generally speaking, you can do it for free.
4. Like others have said - use every way you can think of to get people to visit your site but better still, just talk to them and they'll buy from you!
I hope this helps you. Please bear in mind that it is important not to rush and to get the basics right from the outset.