I can't really give you any advice if I don't know what filter was used or how the image was created.
What kind of camera are you using? You can get used filters for very cheap at your local camera shop for most cameras if the expense is an issue.
Failing that maybe you can re-create this image in photoshop using another filter and then tell me which one was used.Or you can get creative and make your own
Filters are pretty important.