Is there a utility to get IP address from interface?

[James Sinnamon <jps@westnet.com.au>]

Dear debian users,

Is there a utility to simply return the IP address of an interface, say
eth1 or ppp0?  I need something that works like:

$ netutil eth0
144.133.251.117

... or is it necessary to use ifconfig something like as follows:

$ ifconfig eth0 | sed ' ... ' | cut '....' | awk '...'  | .... etc
144.133.251.117

?

TIA

James

PS.  I am doing this all in order to get ddns3 working so any pointers to 
useful docs would be greatly appreciated.
-- 
James Sinnamon
jps at westnet com auStralia
ph +61 412 319669, +61 2 95692123, +61 2 95726357