Coinbase offers public Market Data through REST Endpoints, when you call one of these endpoints, you will get a snapshot of the market data requested.
The Market Data Endpoints don't require authentication, so are freely available to all users.
Example: to get an snapshot of the book BTC-USD, do the following call
oCoinbase := TsgcWSAPI_Coinbase.Create(nil);
ShowMessage(oCoinbase.REST_API.GetPublicProductBook('BTC-USD'));