ASLOOKUP is the tool which searches the sequence of AS number specified 
with the parameter from IRR and indicates the first line of Description 
of AS Object. 

Advantages: 
You can search many AS Numbers at one time. 
You can use result of "show ip bgp" command with CISCO router. 
You can search to ARIN, JPNIC and APNIC whois dabase. 
You can srarch AS Number from IP Addresses. 

WWW: http://www.kk.iij4u.or.jp/~kuniaki/aslookup/index-e.html