Absolutely.Many internet marketers have perhaps hundreds of products on their computers to try and sell or use Clickbank ,CJ, Amazon, Payspree or others to find products to promote.Unless they can get traffic to those products that target keywords that people search for they may as well promote cat toys to dog lovers or marketing products to CocaCola. It can be done but why struggle to sell ice to an Eskimo ?

Regarding templates: In your Word Press dashboard you will see in the left column "Add Themes" .Click that and you will be able to access hundreds of free themes.Choose one that is best for your needs and cilck Install.
Then click Preview.If you like it ,click Activate and from there you may see options.depending on the theme you chose, to change the header,sidebars,add widgets etc.Don't overdo the plug-ins or widgets.You want the site to load fast and not distract "The Message" to your prospective clients.

Since you already have a web site simply go to c-panel on your server,Fantastico, and 3-click install of a Word Press blog attached to your site.Via the blog dashboard you can access hundreds of themes and plug-ins.Right now I am using the Suffusion theme with 3 columns and with it am able to change colours and outlay very easily without needing to use the code editors of the theme.
Initial plug-ins should include:
All-in-one-SEO
Akismet to block spam or "Bad Behavior" plug-in
Google XML sitemap Generator
WordPress-statistics
Auto tags
Auto Tweet to inform people on your Twitter account of new articles
Intense Debate for comments or JsKit comments
MBP Ping Optimizer to ping social sites
Sociable so people can click other social sites about your article
Permalinks to simplify the addresses of your articles rather than default
As I said ,there are hundreds of plug-ins but you want your site /blog to load fast so as not to lose readers.
To add content ,have your staff sing up as members and then in your blog dashboard assign these users as contributors or authors.This will give them limited access to the "add new Post" part of the dashboard where they can use the visual editor to type in or copy/paste an article and click Save .The page reloads and they click "Publish" or Preview 1st before Publishing and voila ,it shows up in the blog as a new post.

This article reminds me of a job finding club I once attended.It was basically a 3 week course on research of the job market, ,not just to see what was available , but how best to present yourself to a prospective employer by knowing your own strengths and weaknesses and knowing exactly how you could help them as an employee by knowing the company and their product and their competition.
On the internet you have to market yourself first ,know your competition, and above all know what the readers want and need before you can approach them as potential customers.What you cannot do yourself learn,work or outsource.My own blog's motto is "Grab on and Either Learn or Teach".
What you have learned ,pass on to others and the rewards are manyfold. Establish yourself as an authority figure and learn to market yourself first
and the customers will ask you for more.
Do not expect this overnight. It takes a minimum of three months of hard work just to get things rolling.