I'm referring to the \"circle"
I've replaced the oil control valve as I believe it could be the source of the leak but can anyone tell me if this other part on the block appears to be leaking? Can anyone tell me what this even is?

 

Why not scrub that entire area and then look at it in a day or two...might be far easier to identify the source(s) of the leak. Since oil tends to 'seep' even a small leak may cover a good-sized area in oil and make it difficult to find the source of the leak.