Here you can share seeds of interest (large oil deposits, many deposits close by, or even something else) pertaining to Buildcraft (link is below).
If you decide to post, please (for ease of sharing) post the seed and the x, y, z coordinates of the location you found (or you can say it's at the spawn). An image isn't required, but it would be nice.
If you didn't manually input the seed, or can't remember what you put in, you can install Single Player Commands (link also below) and get the seed from that. (that's the easiest way I know of, if you know a better way, by all means, inform me) You can find the x, y, z coords by pressing F3 to bring up the debug.
xJoni_Drillx brought up a good point: please give the version of buildcraft you are using to get that particular seed
Buildcraft (all credit for buildcraft goes to SpaceToad)
here is one seed that have a considerable amount of oil spawn in nearly all biomes, one medium deposit geyser near spawn on top of mountains. seed: 6053696595177762295 Buildcraft version: 2.2.5 Minecraft version: 1.8.1
Oils in buildcraft are not spawned by seed but are scattered randomly after map generation, one time I found a seed with a geyser, I saw a hole in the middle of the geyser I went down and found a tunnel leading to a dome underground everything filled with oil but a millinaire village spawned, I felt lazy to destroy it so I delete the map and made another one but the oil was gone
OMG, did you see how big the hole under it is? I think there is a RAVINE going through that place, Its like an oil nuke. :Flint and Steel:
holy **** your right, i spawned like 10 spots away from the geyser and didnt think the seed still worked, so i dug down once and was in a HUGE oil hole, then i looked over and saw the geyser, whoever found this seed, i thank...