you can get this information from uniprot directly. off the top of my head, I can think of the following three options:
- using UniProts REST like interface
- using UniProt batch retrieval service
- using UniProt's SPARQL endpoint (unfortunately it appears to be currently unavailable)
@REST: the following query
http://www.uniprot.org/uniprot/?format=tab&columns=id,organism&query=accession%3AP08646+OR+accession%3AP08645+OR+accession%3AP01119 retrieves organism information for the uniprot accessions P08646, P01119 and P08645 in tab seperated format. Just adapt the query argument "accession%3AP08646+OR+accession%3AP08645+OR+accession%3AP01119" to fit your needs
@batch retrieval service: Paste your uniprot accessions into the text field and hit the retrieve button. Afterwards, follow the link to UniProtKB. There (in the search result) you should see the individual entries matching your uniprot ids. Hit the customize link in the upper left part of the search result view remove all unwanted columns and click save. Finally, use the download link in the upper right corner to retrieve the information in you prefered Format.