Use your current "go-nowhere warehouse" job has a starting point. I don't know where you are located and the type of warehouse it is, but if it's anything like the warehousing and distribution centres that make up the transport/logistic hub (road, rail and air) a couple of kms of from me (Perth, Western Australia) then they are all very hi-tech. There's automation and wireless systems for order-picking and pallet/container tracking and stock/materials handling - all kinds of networking providing all kinds of services - think beyond common data networks. The operational, management and security systems at these places are amazing!
So I'd suggest that you grow your current "industry" knowledge as you develop your networking skills and practice - that way when you do get that CCNA cert you are not pounding the pavements without purpose, you have ideas and a context to your networking. You never know, you may end up at your current employer biut in a smarter role!
3 years for CCNA is very doable. But if you can find a local college/school here
http://cisco.netacad.net/cnams/locators/LocatorMain.jsp that is a Cisco Networking Academy that offers evening classes then you should be able to clear the CCNA in in 1 year - you'll get labs and theory plus do extra well in the last exam and you could get yourself a 50% discount off the cost of the cert exam!
And get yourself on LinkedIn - the savvier recruiters are looking there these days - it's all about (human) networking.
Oh, and don't worry about the age thing - I have 16 to 60 years olds in my networking classes.
Aubrey