Hi, depending on the source of your DNA. From roots we use plant dneasy mini kit (qiagen), for soil (containing extraradical hyphae and spores) PowerSoil dna isolation kit (Mobio). If you want to amplify individual spores you can try to do it directly (either mechanically crushing them or not), but this task can be hard if you are not sure that have "fresh" spores (those collected in the field can be dead or colonized by other fungi and that the rate of successful amplification can be low).
When you get the DNA isolated, you should do a PCR with specific primers, either direct or nested. Check Kohout et al. 2014 Soil Biol & Biochem 68:482-493 to have an overview of the available primer sets.
Once you have the amplified DNA of AMF you can directly sequence them (if the came from individual isolates) or use some fingerprinting techniques: DGGE, SSCP, TRFLP... you have also the option to carry out a massive sequencing (454-pyrosequencing) or direct cloning and sequencing.