I wrote a paper on DNA topology for genetics a couple years ago, so I can offer some references. Not sure how applicable they are to what you're looking for, but it's something. 5 and 9 should describe the folding processes and how they construct them.
1. Mirkin, SM. DNA Topology: Fundamentals. Encyclopedia of Life Sciences. 2001
2. Hardin, AH, et al. Direct measurement of DNA Bending by Type IIA Topoisomerases: Implications For Non-equilibrium Topology Simplification. Nucleic Acids Research. (2011) first published online March 17, 2011 doi:10.1093/nar/gkr109
3. Mikelsen, MB, et al. Pressure-Driven DNA in Nanogroove Arrays: Complex Dynamics Leads to Length- and Topology-Dependent Separation. Nano Letters. (2011) first published online March 1, 2011 doi:10.1021/nl1044764
4. Dorman, CJ and Corcoran, CP. Bacterial DNA Topology and Infectious Disease. Nucleic Acids Research. (2008) first published online December 10, 2008. doi:10.1093/nar/dkn996
5. Dongran, H, et al. Folding and Cutting DNA Into Reconfigurable Topological Nanostructures. Nature Nanotechnology. (2010) first published online October 3, 2010. doi:10.1038/nnano.2010.193
6. Szambowska, A, et al. Coupling and Transcription and Replication Machineries in λ DNA Replication Initiation: Evidence for Direct Interaction of E. coli RNA polymerase and the λO protein. Nucleic Acids Research. (2010) first published online September 9, 2010. doi:10.1093/nar/gkq752
7. Laponogov, I, et al. Structural Basis of Gate-DNA Breakage and Resealing by Type II Topisomerases. PLoS ONE 5(6): e11338. doi:10.1371/journal.pone.0011338
8. Yurke, B, et al. A DNA-fuelled Molecular Machine Made of DNA. Nature 406, 605-608 (10 August 2000) doi:10.1038/35020524
9. Andersen, ES, et al. Self-assembly of a Nanoscale DNA Box With a Controllable Lid. Nature 459, 73-76 (7 May 2009) doi:10.1038/nature07971
10. Ding, B, et al. Gold Nanoparticle Self-Similar Chain Structure Organized by DNA Origami. Journal of the American Chemical Society, 2010, 132 (10), pp 3248-3249 first published online February 17, 2010 doi: 10.1021/ja9101198