select query question to get data?

hi,
I have 3 tables.  Subscriber, Campaign and CampaignSubscriber.
A subscriber can sign up for multiple campaigns and each campaign has multiple subscribers.

Campaign
CampaignId -  (Guid)
Name -  nvarchar
Description nvarchar


Subscriber
SubscriberId  (guid)
Name  nvarchar

CampaignSubscriber  (Junction Table)
SubscriberId (guid)
CampaignId (guid)

Objective 1
After the user signs in I redirect the them to campaign.aspx.
If the Subscriber exists in the Junction table CampaignSubscriber then
I want to show the Campaign Name and description from the campaign table
on campaign.aspx.

Objective 2
If the Subscriber does not appear in CampaignSubscriber  then I want to ...