Here you go..

Best Practices for Disaster Recovery with Symantec Endpoint Protection  [MOST IMP]

http://service1.symantec.com/SUPPORT/ent-security.nsf/docid/2007082112135948

Migrating to Symantec Endpoint Protection 11.0 MR4

http://service1.symantec.com/SUPPORT/ent-security.nsf/docid/2008121712452848

FAQ

http://service1.symantec.com/SUPPORT/ent-security.nsf/docid/2007071909500548

Apart from these go through chapter 8 of the "installation guide" for detailed informaion on migration.

Plan your SEP deployment design based on your location, network...

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If you have a good network infrastructure, You can have one SEPM server and all other servers(which are in location) can be replaced with GUP's
Since you have 2000 clients you can use embedded database.
If you want load balancing features you may have to go for MS SQL.

OR 

You can have multiple sites with replication setup(Like old design one primary server and many secondary servers).
Each sites will have one SEPM and it will replicate the logs and content with primary server.

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For updation...
You can configure primary SEPM server to connect to internet and all other servers will update from primary server.

OR 

You can setup a Liveupdate administrator server which will download the updates from internet and provide it for server's and clients.

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You will find lot of disscussion on individual points mentioned above.

 Hello Uday,

Here is the link for the questions / best practices for migration, It would be good to check sandep salis suggestions :)

https://www-secure.symantec.com/connect/forums/migration-symanec-system-center-configuration-symantec-endpoint-protection

'How To Migrate From Symantec Antivirus System Center Console To Symantec Endpoint Protection Manager'
 http://service1.symantec.com/support/ent-security.nsf/docid/2008110516140048?Open&seg=ent

Top 10 Symantec Best Practices - Deploying Symantec Endpoint Protection Architecture

http://service1.symantec.com/support/ent-security.nsf/docid/2009012721190648?Open&seg=ent

Title: 'Symantec Endpoint Protection Manager reference guide for Symantec System Center users'
 http://service1.symantec.com/support/ent-security.nsf/docid/2007021509381848?Open&seg=ent

Endpoint Security Migration & Installation

http://www.symantec.com/business/support/endpointsecurity/migrate