The RPMs are best installed by just downloading them into a directory and typing "rpm -i *.rpm". For help with this, I recommend Percona's forums or mailing lists - forum.percona.com and groups.google.com/group/percona-dev.
For replication there's not anything really new in the Percona patches. You are best off just looking at the guide in the MySQL manual:
dev.mysql.com/doc/refman/5.1/en/replication-howto.html
For HA recipes, you've basically got the choice of MySQL and/or DRBD. I wrote an article on Percona's mysql performance blog here:
http://www.mysqlperformanceblog.com/2009/07/07/is-drbd-the-right-choice-for-me/
Hope this helps!