Please try all the below links which gives you more information.
To get started..
11g - http://docs.oracle.com/cd/E23943_01/bi.htm
OBIEE 11g architecture...http://www.rittmanmead.com/2010/07/09/obiee-11gr1-architecture-and-use-of-weblogic-server/
Please mark helpfull or correct if it clears
Below are the topics to learn Oracle Business Intelligence Enterprise.
OBIEE and BI Server Architecture.
Data warehouse fundamentals.
Repository basics, structure, features, and functions - Using BI Admin tool.
Building a Physical Layer (Data sources, connection pool, tables, Keys, Aliases and opaque views).
Best Practices to follow while building a Physical Repository.
Building a Business Model (Logical Table, Column, Sources).
Building a time dimension hierarchy and other dimensions.
Defining logical models and building measures.
Learning the Business Model properties.
Building the presentation layer in Repository.
Create Presentation layer objects and setting up appropriate properties.
Testing and validating a repository.
Deploying the repository to the BI Server.
Introduction to presentation services - Answers, Dashboards and Delivers.
Creating reports, filters, formulas, prompts in Answers.
Exploring Charts and graphs in Answers.
Creating multiple views of the same report.
Creating pivot tables and other views.
Dashboard basics and exploring dashboard editor.
III. Security - Administrator
Introduction to Security in BI Admin tool and presentation server Administration.
Creating Users and Groups. Permissions for users and groups.
Setting up different connection pools, Query limits and timing restrictions.
Variables – Repository, Session and Presentation Variables
Advanced concepts in presentation server.
Using variables during design and developments.
And see the below links for your reference,
Obiee 10g Training. Re: Learning OBIEE. The right way. Re: OIEE Training.
Obiee 11g Installation. Re: Weblogic for 11g