Hello,
I too am hooked. I did the Frances last August. I am doing the Portugues this August (starting in Porto and hopefully, this time, ending up in Finesterre and Muxia). Interesting, I did the first four days of the Via de la Plata earlier on this month when I happened to be in Seville for a work thing. If you can understand written Spanish, an excellent guide book is La Via de La Plata a Pie y en Bicicleta: Monumentos, Paisajes, Albergues, Etapas. It is published by El Pais/Aguilar. It was published in 2008 and has a form of ring binding that will allow you (with a bit of effort) to detach the pages you need for the day so that the guide can stay in your pack and the pages you need in a pocket. It has good route maps and very useful info about where to stay.
A top tip for food on the Plata is, if you like pork, the secreto de cerdo iberico. This is a special cut of meat from the patanegra pigs you will see running around from day 3 on. The cut is from the shoulder and it is a marbled meat, so it has fat, but isn't fatty. Since the meat is from the patanegras, it has an amazing taste (i.e. it actually has flavour as opposed to the factory fed pork I can buy in my local supermarket in the UK). Normally is it cooked over a flame, so what you get is a thin cut of meat that is nicely seared on the outside but very juicy on in the inside and very tender. I have never ever heard of this cut of pork before the Via de la Plata. However, once we knew about it, we kept a look out for it in other parts of Spain (like Malaga).
I am glad that you liked the Portugues enough to come back for more. This bodes well for our trip along the Portugues. On the Via de la Plata, of the other 6 peregrinos I met, 5 had done the Frances (one 17 times). They all preferred the Frances as they said that there was more of a Camino spirit. If you haven't done the Frances, it might be a good idea to take the variant that goes to Astorga, where it joins onto the Frances (rather than the Ourense route). This way, you get a bit of both worlds. The guide book I mention above goes via Astorga and suggests 38 days for the entire trip (28 days to Astorga and 10 after). Looking at the stages to Astorga, I think that 28 days is about right. The days are long and there are not that many places where you can put two stages together without feeling very sorry for yourself on arrival. Once in Astorga, the towns are closer together, so it is much easier to nibble away at the 10 days they suggest. It took us 7 days to get from Astorga to Santiago (and we started the last day in Monte Gozo, just to have a nice wee walk to finish things off and arrive in Santiago in plenty of time to get the compostella, make the noon mass and find a place to stay).