With Converter App, you can convert WEBM files into many other formats:
WEBM to MP4 | WEBM to MP3 | WEBM to GIF | WEBM to MOV | WEBM to JPG | WEBM to WAV | WEBM to AVI | WEBM to MKV
→ All WEBM Converters
If you want to keep working with your final OGV, try:
OGV to MP4 | OGV to MP3 | OGV to MOV | OGV to WEBM | OGV to MKV | OGV to AVI | OGV to WMV | OGV to WAV
→ All OGV Converters