In order to display a list of contacts and leads that are associated to a Campaign, you will need to run a "Campaign Call Down Report". This is a canned report located in the Reports tab under the Campaign Reports section.
Once you click on the report link, select a campaign and click on "Run Report" to display all contacts and leads that are associated to that campaign.
If you don't have this already, you can place a shortcut link in campaign Custom Links section to go directly to the report. To do so, follow the steps below:
1. Click on:
Setup | App Setup | Customize | Campaigns | Buttons, Links and Actions.
2. Create a new link and label it "View All Campaign Members".
3. Select URL as the Link Type, then click "Next".
4. Paste the following into the Link URL section:
5. Follow the rest of the steps in the wizard and then click "Save".
6. Then click on the Page Layouts link below Campaigns.
7. Click on "Edit" next to the page layout.
8. Scroll down to the Custom Links section.
9. In the floating box to the right, change the view from "Campaign Fields" to "Campaign Custom Links".
10. Click and drag the "View All Campaign Members" field into the Custom Links section.
11. Click "Save".
You should be able to find this link in the Custom Links section inside a campaign. Each time you click on this link, it will bring you directly to the "Campaign Call Down Report" displaying members of the campaign.